1. Area of the Art
The present invention relates generally to vessels handling methods and systems used in conjunction with automated chemical analyzer instruments and, more specifically, to methods and systems for picking and placing vessels used in conjunction with automated chemical analyzer instruments.
2. Description of the Prior Art
Automated chemical analyzers, particularly immunodiagnostic instruments, are widely used in clinical chemistry sampling and analyzing applications. The instruments often involve the handling of vessels for performing various assays. The basic functions of handling vessels typically involve picking, transferring, and placing the vessels, and mixing their contents for processing and analyzing by an automated chemical analyzer. During the transfer process, the vessel and its contents must be moved smoothly. Jarring the vessel may cause the contents to either splash out of the vessel, or if splashing does occur, droplets may stick to the walls of the vessel at the top. Either of these events may affect accuracy of the results.
The following references are found to be pertinent to the field of the present invention:
U.S. Pat. No. 2,899,232, issued to Walter, Jr. on Aug. 11, 1959, disclosed a bottle chuck adapted for handling bottles. The bottle chuck has a series of threadedly connected cylindrical pieces and jaws for engaging bottle necks and a spring-loaded piston rod for engaging the bottle caps.
U.S. Pat. No. 3,554,594, issued to Thoma on Jan. 12, 1971, disclosed a pneumatically-operated gripper for bottles. The gripper has a plurality of fingers bound by a sleeve, such that the upward movement of the sleeve will engage the fingers and a downward movement of the sleeve will release the fingers.
U.S. Pat. No. 4,257,639, issued to Stock on Mar. 24, 1981, disclosed an ejector device for ejecting a store from an aircraft store rack. The device includes lug-retaining fingers and a collar for holding the fingers in engagement with a lug mounted on the store. Removing the collar causes the fingers to disengage from the lug for releasing the store.
U.S. Pat. No. 4,611,846, issued to Feiber et al. on Sep. 16, 1986, disclosed a gripper head for attachment to a vertical axis of a robot or a pick-and-place machine for picking up components and placing them on a workpiece. The gripper head has two opposite piston and cylinder units, and two opposite jaws, each driven by a respective piston and cylinder unit to move in a transverse direction for gripping the components.
U.S. Pat. No. 4,705,311, issued to Ragard on Nov. 10, 1981, disclosed a component pick and placement spindle assembly for surface mounting and insertion of electrical components. The assembly includes a mechanism for squaring the component to an orthogonal coordinate system and also an orienting means comprising a direct drive rotary motor operatively associated with a tool assembly having component engaging fingers.
U.S. Pat. No. 4,810,018, issued to van de Ven et al. on Mar. 7, 1989, disclosed a gripping device for placing electrical or electronic components with terminal pins on a substrate. The gripping device has a pair of grippers movable to one another to close and open their jaws, and a spring-loaded abutment means for pressing the pins of the component into the respective holes on the substrate.
U.S. Pat. No. 4,892,344, issued to Takada et al. on Jan. 9, 1990, disclosed a parallel gripper used for gripping a work for a robot. The gripper has a fluid pressure actuator having two pistons, two transversely slidable fingers, and a power transmission mechanism having two levers each connected between the two pistons and also to one of the fingers.
U.S. Pat. No. 5,236,239, issued to Govang et al. on Aug. 17, 1993, disclosed an adapter for a pick-up device having a plurality of fingers extending from one end of a hollow member, and an apparatus for releasable engagement and transport of an object. The adapter has a first portion for insertion into the hollow member, a stopping portion for limiting the insertion, and a second portion for receiving the object.
U.S. Pat. No. 5,295,723, issued to Kronseder on Mar. 22, 1994, disclosed a gripping bell for bottles. The gripping bell includes a sleeve-like collect chuck having elastic fingers slidably movable by an actuating element for gripping the head of a bottle.
U.S. Pat. No. 5,775,755, issued to Covert et al. on Jul. 7, 1998, disclosed a tube gripper device having a plurality of fingers. The gripper has a cam connected to a solenoid actuator for spreading the fingers apart and a resilient means for returning the fingers.
U.S. Pat. No. 5,948,360 issued to Rao et al. on Sep. 7, 1999, disclosed a modular vial autosampler. The autosampler includes a base unit, a thermal block having a passage way for fluid circulation, a vial rack positioned over the thermal block in heat-conducting relation, and a vial transporter including a main arm projecting from the base unit along a first axis and transportable along a second axis which is perpendicular to the first axis and having a vial gripper assembly mounted on the main arm and transportable along the first axis with a gripper head movable along a third axis perpendicular to both the first axis and second axis.
One of the disadvantages of many conventional vessel picking and placing devices used in conjunction with automated chemical analyzers is that they often have very limited capacities. For example, the prior art devices are often not designed to pick up misaligned vessels. In addition, the prior art devices are often not designed to transfer the vessels in an upright position and mix the contents contained in the vessels in the same cycle. Furthermore, the prior art devices are often not designed with a mechanism to ensure that the vessels are correctly seated before releasing them from the grippers.
Therefore, it is desirable to provide a new method and system for picking and placing vessels which can be used in conjunction with automated chemical instruments and also overcome the disadvantages of conventional methods and systems for handling vessels. Particularly, it is desirable to have methods and systems capable of picking misaligned vessels, and ensuring the vessels are correctly seated before releasing them from the grippers when placing the vessels to avoid jarring or splashing their contents. In addition, it is desirable to have methods and systems capable of transferring the vessels in an upright position and mixing their contents in the same cycle.